Fire door or shutter



ALLAN S. BARROWS, 0F CHICAGO, ILLINOIS.

FIRE DOOR 0R 'SHUTTERh Specification of Letters Patent. Patented Jne 27, 1922 Application ined February 4, 1920. serial No.,356,224.

To all whom t may concern Beit known that I, ALLAN S. BARRoWs, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Fire vDoors or Shutters, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to improvements in lire doors or shutters.

One object of the invention is to provide an improved fire door or shutter composed principally of sheetl metal wherein great strength and rigidity per. unit of weight is obtained.

Other objects of the invention are to provide a fire door or shutter of the character indicated which will effectively withstand disintegration, warping and twisting; which will minimize the transference of heat; vand which will be of neat and pleasing appearance.

In the drawings forming a part of this specification, Figure 1 is an elevational view of a fire door showing one embodiment `of my invention. Figure 2 is a vertical sectional view taken vsubstantially on Vthe line 2-2 of Figure 1. Figure 3 is a `horizontal sectional view taken substantially on the line 3 3 of Figure 1. -In both Figures 2 Vand 3, the door is shown associated with a building wall or partition so arranged as to adapt the door for sliding movement vertically. Figure 4 is a View similar to Figure 3, upon an enlarged scale, parts being broken away, and illustrating thev manner in which the door would be used withy a building wall or partitionwherein the dooris slid in front of the opening and moved partly thereinto with the edges or periphery of the door in contact with the wall or artition. Figure 5 is a view similar to Figure 4 illustrating a somewhat different construction of door, the arrangement being of that character where the door is adapted to slide horizontally within a suitable recess provided therefor within the building wall or partition.

` In said drawings and referring tothe construction illustrated in Figures 1, .2 and 3, my improved door is shown as comprised lbroadly of an outer wall designated by the letter A, an inner wall designated by the letter B, peripheral or marginal binding sections, E, E and strlips C', and tire-resisting or insulating spacing strips D. f

In. carrying out my invention, I preferably form each wall of a plurality of sheet metal sections of comparativelythin gauge.v Preferably, also, each wall of the door, 1nner and outer, is of similar construction. As shown, I have formed each wall of three E, the same having their edges overlapped and rigidly united either by spot-welding or by riveting, the use of rivets being illustrated in the drawings as indicated at 10.

In order to obtain maximum strengthand rigidity with comparatively thin gauge sheet metal, each wall ofthe door is provided with vertically extendin edge corrugations 11-l1, a center vertlcally extending corrugation 12, topl and bottom edge corrugations 13 and 14, anda plurality of intermediate horizontally extending corrugations 15-15.f

The edge corrugations 11, `13 and 14 are placed relatively close to and preferabl parallel with the peripheral edges of each7 wall, thereby to each wall four sides.l

It is desirable to maintain the two walls of the door in spaced relation so as to thereby obtain a dead air space between the two walls of the door and thus prevent undue circulation and alsoA minimize the transference of heat from one side of the door to the other. In this manner, if one side or wall of the door is subjected to intense heat, the effects thereof will be substantially confined to that particular side or wall of the door and the opposite side or wall of the door left intact and with the necessary strength and rigidity, combined with the frame-forming binding strips, to support the wall of the door which is directly subjected to the heat. To accomplish this result, I provide a plurality of the spacing strips D, preferably four of the same. These strips D extend leaving a at marglnal portion as indicated at 16 around all` vertically and two of, them are locatedl at the lire-resisting com-v `more distant parts of the door.

non-warping construction, I employ the binding strips C around all four edges, each of the strips C being preferably composed of sheet metal and bent to U cross section so as to fit over and substantially seal the edges of the two walls of the door. The edge re-enforcing members C are secured to the walls of the door in any suitable manner,7 preferably by riveting as indicated at 1 In actual practice, the gauge of the metal will approximate 13;,- inch to 2, inch and the depth of the corrugations 11, 12, 13 and 14 will be approximately 1% inches, so that the over-all thickness o-f the doo-r will be slightly more than 3 inches. This provides a door which can-readily be used in building walls or partit-ions of average construction.

It Will be noted that all of the corrugations orequivalent strengthening indentations, extend outwardly from the plane of the re-spective wall of the door. Furthermore, these corrugations are merged at right angles to each other, as shown in the drawing, thereby producing great strength because of the fact that the horizontal corrugations will-brace the vertical corrugations against collapse and vice versa. The arrangement of corrugations is also such that each wall of the door is individually and independently well adapted to resist strains imposed externally upon it in any direction, either perpendicular to the door or perpendicular to the side edges or erpendicular to the top and bottom edges. urthermore, the corrugations serve an. additio-nal function in that they are individually adapted to compensate for expansion which may take place in the door at different portions thereof. That is to say, the horizontal corrugations are well adapted to compensate for internal Stresses set up in the metal which tend to eX- pand the metal in a vertical direction, and such compensation may be said to be localized with respect to, each adjant pair of horizontal corrugatipns. Similarly, internal stresses set up within the metal tending to expand the metal horizontally will be compensated for 4by the vertical corrugations. Stated in another manner, it will be observed that each wallof the door is divided into a series of-what may be termed rectangular panels each of which is surrounded by cor- `rugatious extending vertically and horizontally. If it be assumed that intense heat is ap-plied to any one of said panels and ex-y pansion is neceary, it is evident that such expansion will be taken up or localized within the four surrounding corrugations, thereby preventing the transference of warping or twisting or disintegration to other Such expansion as does occur in either wall of the door will be in a direction tending to sep-arate that particular wall of the door from the other wall thereof and hence will prevent the tWo walls from coming into contact over extended areas which would defeat the purpose of the dead air space and permit communication of the heat from one wall to the other without any material interference. By providing the inherent strength and rigidity in each wall of the door, heretofore mentioned, it is evident that they are mutually adapted to sustain each other and in the event that one wall is subjected to very intense heat causing distortion `or softening thereof, nevertheless the other wall will still retain the requisite strength to sustain the weight of the distorted Wall.

In the construction shown in Figure 4, the door is made as illustrated in Figures 1, 2 and 3 and need not be re-described. Figure 4 is shown merely to illustrate how the door may be positioned with respect to the wall 20 with the multi-ply marginal portions of the door lying against the wall.

In the construction shown in Fig. 5, the two walls of the door and the strengthening Corrugations and indentations are the same as illustrated in Figures 1, 2 and 3. In this form of the door, however, the edges of the walls are framed and united by T-shaped members C". The webs of the T-shaped membersC, as indicated at 21, are interposed between the fiat marginal sections 116 'of the walls and the three plies preferably riveted as indicated at 117. The flanges 22 of the T-shaped members C are extended perpendicular to the general plane of the door and are preferably of an o-ver-all width corresponding to the over-all thickness of the door proper. In the construction shown in Figure 5, the T-shaped members C are well adapted to co-operate with the wall or partition to form an effective seal therewith and thereby prevent air from circulating around the edges of the door. In the construction shown in Figures 1, 2 and 3 this function is served by the edge corrugations 11, 13 and 14 of the door which are preferably seated within corresponding recesses in the building wall or, partition. In the construction shown in Figure. 5, due to the use of the T-shaped members C the outer vertically extending spacing strips are omitted but the intermediate spacing strips D are. retained.

I have herein shown and described what I now consider the preferredpmanner of carrying out my invention, but the same is merely. illustrative and I contemplate all changes and modifications that come ywithin the scope of the claims appended hereto, and: in this connection it will be observed that I have illustratedl my invention as employed in a door only although the invention is obviously capable of use'in a shutter or the like, and this I consider within the scope of my invention.

I claim:

l. In a fire-resisting door or shutter, the combination with inner and outer sheet metal walls, said walls having their edges overlapped and rigidly' united, each wall having a flat marginal portion, each of said walls being provided with a plurality of.

outwardly-extended integral corrugations dividing the wall into a plurality of panels, each outlined by corrugations adapted to locally compensate for expansion of the metal in any direction in the general plane of the wall, the panels of one sheet metal wall being disposed opposite the corresponding panels'of the other sheet metal wall and separated and disconnected therefrom. f

2. In a lire-resisting door or shutter, an inner wall and an outer wall composed of sheet metal and united around their periphf eries, each of said walls having a flat marginal portion and provided within the area of said flat marginal portion with corrugations extending outwardly from the plane of the fiat marginal portions and arranged transversely and lengthwise of the wall and merging with each other, the corrugations exte-ndin lengthwise being adapted to compensate or lateral expansion and the transversely extending corrugations being adapted to compensate for vertical expansion of the metal, within said marginal portions, said corrugations also adapting each wall individually to resist internal stresses set up tending to buckle or warpfthe respective wall.`

3. In a fire-resisting door or shutter, the combination with an inner sheet metal wall, of an outersheet metal wall, and metal frame-forming members extending around the peripheries of the walls and rigidly united therewith to form substantially sealed edges for the door or shutter, each of said walls being provided with a plurality of intersecting corrugations to thereby form each wall into a series of panels with each panel outlined by corrugations, said two .walls being spaced apart to provide a dead air space therebetween, all of said corrugations terminatin inside of the area defined by the frameormin members.

4. In al fire-reslsting door or shutter, the combination with inner and outer sheet metal walls, each wall having a lat marginal portion and provided with outwardlyextending corrugations within the area defined by said flat marginal portions, said corrugations being arranged lengthwise and ripheries of the' two walls and rigidly,

united with the said flat marginal portions of the latter to form a substantially sealed multi-ply edge-frame.

In a re-resisting door or shutter, the combination with inner and outer walls rigidly united around their peripheries,` each of said walls consisting of a plurality of sections of sheet metal having adjacent edges overlapped and walls being similarly corrugated, each wall having corrugations extending along each edge thereof and a series of corrugations merging with and extending transversely between a pair of the `edge corrugations; land means for spacing said walls apart to thereby provide a dead air space.

6. In a fire-resisting door or shutter, the combination with inner and outer sheet metal walls, each of said walls being composed of a plurality of sections having adjacent edges overlapped and rigidly united, each wall having a fiat marginal portion and provided with outwardly extended corrugations withinv the area defined by the said flat marginal portions, said corrugations b'eing arranged lengthwise and transversely of the wall and merging with each other; spacing strips interposed between the walls of the door; and frame-forming members extending around the peripheries of the two walls and rigidly united with the said flat marginal -portions of the latter to form a substantially sealed multi-ply edge-frame.

7. In a lire-resisting door or shutter, the combination with outer and inner sheet rigidly united, said metal walls, of combined frame-forming and edge-uniting members rigidly united with the edges of said walls, each of said walls being provided with a plurality of\ outwardly extended integral corrugations di4 viding the wall into a plurality of panels each outlined by corrugations adapted to locally compensate for ex ansion of the Inet-al in any direction int e plane of the 

